Automated paving machine

ABSTRACT

A compact self-propelled paving machine whose hopper, for receiving asphalt or other paving material therein, discharges the paving material rearwardly of the supporting drive wheels of the machine and directly upon the surface to be paved. The drive wheels, as well as motive means and drive mechanism connecting the motive means to the drive wheels, are so compactly arranged that the hopper substantially entirely overlies the same. Such compact construction facilitates positioning a standard size dump truck, or a larger so-called tandem-wheel dump truck, in such close proximity to the hopper that the paving material can be dumped directly from the truck bed into the hopper and discharged from the lower portion of the same hopper directly upon the surface to be paved, thereby obviating the need for intervening conveyor means for transferring the dumped paving material to the point at which it is discharged onto the surface to be paved. The machine also includes distributing augers, discharge gate means, a vertically movable screed and extensible and retractable screed extensions, all of which, in addition to the drive mechanism for the drive wheels, are automatically controlled by an operator at a convenient centralized location on the machine during the paving operation.

United States Patent 1191 Lee July 3, 1973 AUTOMATED PAVING MACHINE [76]Inventor: Billy R. Lee, PO. Box 8433, [57] ABSTRACT Charlotte 28208 Acompact self-propelled paving machine whose hop- [22] Filed: Aug. 9,1971 per, for receiving asphalt or other paving material therein,discharges the paving material rearwardly of [21 1 App! l70l09 thesupporting drive wheels of the machine and directly upon the surface tobe paved. The drive wheels, as well [52] U.S. Cl. 404/84 as motive meansand drive mechanism connecting the [51] Int. Cl. E0lc 19/48 motive meansto the drive wheels, are so compactly ar- [5 8] Field of Search 94/46,44, 45, 50 P ranged that the hopper substantially entirely overlies thesame. Such compact construction facilitates posi- [56] References Citedtioning a standard size dump truck, or a larger so-called UNITED STATESPATENTS tandem-wheel dump truck, in such close proximity to 3 482 49412/1969 Jennings 94/46 R the hpper that Paving material can be dumped3:183:803 5/1965 Gierhart 94/46 R x the truck bed PP and 3,229,6011/1966 Philpott 94/46 R x Charged from the lower POrtiOfl 0f the Samehopper 2,5 ,39 2 1952 Trampler 94 4 R rectly upon the surface to bepaved, thereby obviating 3,031,938 5/1962 Bero 94/45 R X the need forintervening conveyor means for transfer- ,5 5 96 eama 4 9 /50 P ring thedumped paving material to the point at which 1,702,666 2/ 1929Nickel'son-m 94/46 R X it is discharged onto the surface to be paved.The ma- 3329314 4/1962 e 94/46 R X chine also includes distributingaugers, discharge gate 2 means, a vertically movable screed andextensible and 1'652'434 12/1927 94] R retractable screed extensions,all of which, in addition 1 9/1959 carpenterm 94,44 X to the drivemechanism for the drive wheels, are auto- 3,2ss,041 11/1966 Layton 94/46R matically controlled y n Operator at a Convenient 3, 7 317 7 1972Martens M 94/4 centralized location on the machine during the pavingPrimary Examinew-Nile O. Byers, Jr. Attorney--Parrott, Bell, Seltzer,Park & Gibson operation.

12 Claims, 18 Drawing Figures 1 July 3,1973

United States Patent Lee.

\5 MOQr I 6 1i 8 U 24 a 25 47 MN; l0

PATENTED JUL 3 9975 ME! 1 if Q AUTOMATED PAVING MACHINE BRIEF SUMMARY OFTHE INVENTION Some paving machines or spreaders which are of the typeattached to and propelled by a truck or other vehicle during pavingoperations, are so constructed that the rear portion of a truck bed mayoverlie the hopper of the paving machine to facilitate dumping orotherwise transferring the paving material from the truck bed directlyinto the hopper and onto the usual distributing auger means thereofadjacent the discharge opening of the hopper through which the pavingmaterial is discharged directly upon the surface to be paved. Variousforms of self-propelled paving machines also have been proposedheretofore having hoppers from which paving material is discharged ontoa surface to be paved during the paving operation. However, in suchproposed self-propelled paving machines, following the transfer ordumping of the paving material from a truck onto the paving machine,various encumbrances, such as drive motors, control mechanisms anddriving connections from the motors to the drive wheels, augers andother operating components of the self-propelled paving machine, haverequired that further handling or conveyance of the transferred pavingmaterial had to be effected in order to deliver the paving material tothe point at which the paving material is discharged from the pavingmachine onto the surface to be paved. Generally such further conveyanceor handling of the previously transferred paving material has beeneffected by means of a conveyor belt or belts extending from a front endhopper of the paving machine to a rear end hopper or other means fordischarging the paving material onto the surface to be paved. It hasalso been proposed to utilize a tiltable or otherwise movable skip,large bucket or other container positioned adjacent the front end of apaving machine for receiving paving material therein from a truck, andwherein such skip, large bucket or container is operated by a hoist orthe like for subsequently transferring the paving material rearwardlyinto a hopper having a discharge opening in its lower portion fordischarging the paving material received therein onto the surface to bepaved.

It is an important object of this invention to provide an improved,self-propelled paving machine or spreader which is compact, highlyefficient and selfcontained and eliminates the aforementioned and otherdisadvantages of self-propelled paving machines proposed heretofore.

It is another object of this invention to provide a selfpropelled pavingmachine having two substantially axially aligned sets of drive wheelssupporting the same for movement overthe surface to be paved anddisposed beneath the hopper thereof, which sets ofwheelsare motor-drivenand are manually controllable independently of each other to not onlyfacilitate steering the paving machine, but to also facilitate turningthe entire machine about a substantially centrally disposed verticalaxis located about midway between the two sets of drive wheels.

Still another object of this invention is to provide a self-propelledpaving machine having motor-driven distributing augers in the opposingside portions of the hopper thereof and which are manually controllableindependently of each other, and wherein, upon the torque load on oneauger becoming substantially greater than that on the other auger, thespeed of the other auger automatically increases relative to that of Isaid one auger. Also, the other auger will continue to rotate eventhough the torque load on said one auger may be such as to stop therotation thereof.

It is another object of this invention to provide an improvedself-propelled paving machine having a vertically movable screed on therear portion thereof with power means for raising and lowering thescreed, which power means is manually controllable by an operatorregardless of whether or not the machine is in the performance of apaving operation.

Still another object of this invention is to provide a paving machinehaving a main screed on the rear portion thereof which is provided withtelescoping screed extensions and associated sled members, and whichincludes power means for adjustably extending and retracting the screedextensions relative to the main screed. The power means is manuallycontrollable so that either or both screed extensions and associatedsled members thereof may be adjusted relative to the main screed, evenduring the performance of a paving operation.

BRIEF DESCRIPTION OF THE DRAWINGS Some of the objects and advantages ofthe invention having been stated, other objects will appear as thedescription proceeds, when taken in connection with the accompanyingdrawings in which FIGS. 1 and 2 are respective front and rearperspective views of a preferred embodiment of the paving machine ofthis invention;

FIG. 3 is an enlarged left-hand side elevation of the paving machinelooking at the lower left-hand side of FIG. 2 and showing the same inassociation with the rear lower portion of a standard size dump truck;

FIG. 4 is a top plan view of the paving machine;

FIG. 5 is an enlarged plan view similar to FIG. 4, but wherein thehopper lower wall means has been removed to expose the drive wheels, themotive means, connections between the motive means and the drive wheels,the various other parts of the paving machine over which the lower wallmeans normally extends;

FIG. 6 is a vertical sectional view taken substantially along line 6-6in FIG. 5, but including the hopper lower wall means and showing thetruck bed receptor thereof occupying a normally lowered positionpreparatory to reception of the lower rear portion or chassis of a trucktherein, as in FIG. 3;

FIG. 7 is a view similar to FIG. 6, but wherein the receptor occupiesfully raised position for dumping any paving material which may haveaccumulated thereon onto the inclined bottom wall panel of the hopperlower wall means; I

FIG. 8 is another view similar to FIG. 6, but is taken substantiallyalong line 8- -8 in FIG. Sand shows the v I I entire lower wall means ofthe hopper occupying a gaging and disengaging a respective set of drivewheels relative to the corresponding drive mechanism;

FIG. 11 is a fragmentary sectional plan view taken substantially alongline 1111 in FIG. 10, showing the clutch means for both sets of drivewheels;

FIG. 12 is a fragmentary elevation, partially in section, takensubstantially along line 12-12 in FIG. 11;

FIG. 13 is an enlarged fragmentary vertical sectional view takensubstantially along line 1313 in FIG. 11;

FIG. 14 is an enlarged, exploded, perspective view of the hopper andmain frame disassociated from the remainder of the paving machine;

FIG. 15 is a schematic diagram of fluid pressure circuits for the pavingmachine;

FIG. 16 is a view similar to FIG. 6 showing a modified form of thepaving machine;

FIG. 17 is a fragmentary view looking up, along line 17-17 in FIG. 16,at the modified means for raising and lowering the truck bed receptor;and

FIG. 18 is a fragmentary view of modified drive means for the augers,and taken substantially along line 18-18 in FIG. 16.

DETAILED DESCRIPTION MAIN FRAME Referring more specifically to thedrawings, the numeral 20 broadly designates a main frame supported formovement over the ground or a surface to be paved by means of right-handand left-hand sets of drive wheels 21, 21a and a front support means, inthe form of a swivelling pair of wheels or casters 23. A hopper 24 issupported by frame 20, and screed means 25 is positioned adjacent therear portion of hopper 24 for smoothing and compacting paving materialbeing discharged from hopper 24 as the paving machine moves forwardlyover the surface to be paved.

As best shown in FIGS. 1, and 14, main frame 20 comprises an elongatemain or front end frame member 20a which is about the same length as thecorresponding length of the hopper 24 measured transversely of thenormal direction of travel of the paving machine. The front ends of aplurality of spaced apart bridging frame members 20b are connected tofront frame member 20a and their rear portions are connected to anintermediate frame member 20c spaced rearwardly from and extendingsubstantially parallel with main frame member 20a. The forward portionsof right-hand and left-hand sets of wheel-mounting frame members 20d,20d are suitable secured to frame member 20c, and a relatively largerrearwardly extending middle frame member 20a is connected at its frontend to a medial portion of frame member 200. A relatively small platform20f is suitably secured upon the middle frame member 20c and the twoadjacent wheel-mounting frame members 20d, 20d straddling the same.

The sets of drive wheels 21, 21a are keyed or otherwise suitably securedon respective axles or shafts 26, 26a journaled in respective sets ofbearings 27 (F IG. 8) and 27a (FIG. 3) suitably secured to the lowersurfaces of the respective sets of frame members 20d, 20d (FIGS. 5, 8and 14).

DRIVE MECHANISM FOR DRIVE WHEELS A motive means, which may take the formof an internal combustion engine 30, is suitably secured on a frontright-hand corner portion of main frame 20 immediately rearwardly offront frame member 20a (FIGS. 1 and 5) and is operatively connected todrive wheels 21, 21a through a drive mechanism including a compositefluid pressure pump means 31 to which the drive shaft of motor 30 isdrivingly connected. Referring to FIG. 15, it will be observed that pumpmeans 31 includes two pump units 31a, 31b which are components ofrespective first and second fluid pressure circuits, but whose inletsare connected to a common source of fluid in an L-shaped reservoir ortank 32 suitably secured on a left-hand front corner portion of mainframe 20 immediately rearwardly of front frame members 20a (FIGS 1, 2,5, 8 and 15).

A conduit means 33 connects the outlet of pump unit 31a to a highpressure manifold 34 having branches 34a, 34a extending therefrom torespective manually operable, four-way, control valves 35, 35a, withbuilt-in bypasses and each having respective sets of outlet conduits a,b, c extending therefrom. Control valves 35, 35a may be of a well-knowntype, such as Model CP valves as manufactured by Gresen Hydraulics,Minneapolis, Minn., for example. Pump means 31 may be of a type known asa Model DCB-6-4.5 as manufactured by said Gresen Hydraulics, forexample.

Conduits a, b of valves 35, 35a are connected to opposite sides ofrespective reversible fluid-operated motors 36, 36a drivingly connectedto the respective sets of drive wheels 21, 21a. A torque limiting meansis common to both sets of drive wheels 21, 21a so that they normallywill rotate in the same direction (either forwardly or rearwardly) atthe same speed. To this end, the output shafts of the fluid-operatedmotors 36, 36a are substantially axially aligned, extend toward eachother, and are coupled together by means of a torque limiter 40, whichmay be of any desired or conventional construction, to normally causethe shafts of both motors 36, 36a to rotate in fixed relationship, butwhich permits either motor shaft to override and rotate relative to orindependently of the other motor shaft upon the torque load on eithershaft becoming substantially and predeterminedly greater than that onthe other shaft. This may occur, for example, upon obstruction ofrotation of one set of drive wheels only, as in the event of one set ofdrive wheels engaging a large rock or other obstruction in its path, andthe other set of drive wheels not being obstructed. This will also occurupon one set of drive wheels being subjected to a predetermined greaterdriving force than the other set of drive wheels or the one set beingdriven in the opposite direction from the other set through manualmanipulation of control valves 35, 35a.

The torque limiter is desirable because the response of the two motors36, 36a to a given or like amount of fluid pressure may not be the same,or a relatively small variation in the torque load on either motorrelative to the other might otherwise cause one set of the drivewheels21, 21a to rotate faster than the other set and thereby turn thepaving machine away from its intended path, unless the operator madefrequent exacting compensating changes in the state of control valves35, 35a. Obviously, the need for such frequent and exacting manualoperation of the control valves would be arduous and might divert theoperators needed attention from the performance of other tasks.

In an actual machine constructed according to this invention, thefluid-operated wheel drive motors were of a type manufactured by saidGresen Hydraulics under their Model No. 1016 and each motor 36, 36a

had an output rating of about 150 foot-pounds torque. A torque limiter40 of a type manufactured by Morse Chain Company, Ithaca, N.Y., undertheir Model No. 35OA-1 was utilized and was adjusted to interrupt thefixed relationship between the shafts of motors 36, 36a upon occurrenceof a torque differential therebetween of about 30 foot-pounds.

Conduits c extend from valves 35, 35a to an exhaust manifold 38connected by a conduit 39 to reservoir 32 to return the fluid beingpumped by unit 31a to reservoir 32 when the wheels 21, 21a are not beingdriven.

To drivingly connect fluid-operated motors 36, 36a to the respectivedrive wheel shafts 26, 26a, the drive shaft of each motor 36, 36a has asprocket wheel 37 fixed thereon (FIGS. 5 and and engaged by an endlesssprocket chain 37a. Chain 37a extends forwardly and engages a relativelylarger sprocket wheel 37b. Each of the two sprocket wheels 37b ismounted on a respective jack shaft 370 joumaled on adjacent bridgingframe members b and is in fixed axial relation to a relatively smallersprocket wheel 37d. An endless sprocket chain 37e engages each sprocketwheel 37d, extends rearwardly therefrom and is mounted on a relativelylarger sprocket wheel 37f.

Each sprocket wheel 37f is suitably secured to one end of a hub orsleeve 42a of a corresponding clutch mechanism broadly designated at 42(FIG. 13). Sprocket wheel 37f and its hub 42a are rotatably mounted on abushing 37g rotatably mounted on the respective drive wheel shaft oraxle 26, 26a. I-Iub 42a is of square or polygonal exteriorcross-sectional configuration and matingly receives thereon a clutchslide 42b which is shiftable between the engaged solid-line anddisengaged broken-line positions of FIG. 13. Thus, slide 42b rotateswith hub 42a and sprocket 37f whenever they are being driven by thecorresponding motor 36 or 36a.

It should be noted that the proximal ends of axles 26, 26a are spacedapart from each other, and the inner end of each axle 26, 26a has aclutch block 420 positioned thereagainst and welded or otherwisesuitable secured thereto. The size and configuration of the periphery ofeach clutch block 420 corresponds substantially to that of thecorresponding hub 42a so that, when the clutch slide 42b occupies itsinnermost position, remote from the corresponding sprocket wheel 37f,the clutch slide 42b bridges, and establishes a driving connectionbetween, the hub 42a of sprocket wheel 37f and clutch block 42c to drivethe corresponding axle 26 or 26a, as the case may be.

In order to shift each clutch slide 42b between the engaged anddisengaged positions shown in respective solid and brokenlines in FIG.13, each clutch slide 42b is provided with a peripheral groove 42dtherein which is engaged by a pair of substantially diametricallyopposed followers on the arms of a corresponding yoke 42f. As best shownin FIGS. 11 and 12, the two yokes 42f are mounted for lateral slidingmovement, parallel to the axis of axles 26, 26a, on a bar 42g whoseopposite ends are suitably secured to blocks 42!: projecting rearwardlyfrom frame member 200. A bifurcated portion 42i of each yoke 42f isengaged by a radially extending finger 42j on the rear end of acorresponding shipper shaft 42k.

The shipper shafts 42k are joumaled in and extend through frame members20a, 20c, and the forward ends thereof are provided with suitablerespective shipped hand cranks 42m positioned adjacent the front surfaceof front frame member 20a so as to be readily accessible for shiftingeach of the clutches 42.

During self-propulsion of the paving machine, as during movement thereofrelatively short distances of, say up to one mile, between paving sites,and during paving operations, both clutches 42 occupy operativepositions, with the respective clutch slides 42b thereof occupying thesolid-line position of FIG. 13 and as shown in FIGS. 11 and 12. However,when the paving machine is to be moved substantial distances, such asseveral miles from one paving site to another, both clutch slides 42bmay be manually moved to the inoperative position to permitfree-wheeling of the drive wheels 21, 21a by a truck or other pullingvehicle. Such freewheeling of the drive wheels relieves the entire drivemechanism from any load thereon during travel of the paving machine fromone location to another and thereby avoids unnecessary wear of the drivemechanism, since the axles 26, 26a then may rotate without impartingrotation to the corresponding sprocket wheels 37f.

To further facilitate moving the paving machine substantial distanceswhile clutches 42 are disengaged, a bracket 23a, to which the casterwheels 23 (FIGS. 1, 3, 6, 7 and 8) are connected for steering movementabout a substantially vertical axis, is suitably secured to and extendsforwardly from front frame member 20a and has a forwardly and rearwardlyextending tubular draft bar-receiving coupler 23b fixed on a forwardportion thereof. A conventional draft bar, not shown, and connected tothe rear end of a truck or other vehicle, thus may be inserted in theforward portion of coupler 23b and held therein by means of a pin orbolt extending through an opening 230 through coupler 23b to facilitatepulling the paving machine substantial distances. Of course, the draftbar may be removed from the coupler 23b when the paving machine is beingmoved from place to place under its own power and during pavingoperations.

HOPPER CONSTRUCTION The compact arrangement of frame 20, drive wheels26, 26a, main drive motor 30, reservoir 32 and the drive mechanismbetween motor 30 and drive wheels 26, 26a facilitates so constructinghopper 24 that it substantially completely overlies the frame, drivewheels, main drive motor, reservoir and the drive mechanism betweenmotor 30 and drive wheels 26, 26a, with the paving material beingdischarged from the hopper 24 closely adjacent and rearwardly of drivewheels 26, 26a directly onto the surface to be paved.

As best shown in FIGS. l-4, 6-8 and 14, hopper 24 comprisessubstantially upright rear end wall means 240, spaced side wall means24b, 24c, and a lower wall means broadly designated at 44 and definingthe bottom of hopper 24. The rear edges of side wall means 24b, 240 arewelded or otherwise suitably secured to opposing side edges of rear endwall means 24a, and the lower portions of side wall means 24b, 24c, aresuitably secured to the outer surfaces of the distal frame members 20d,20d. Since paving machines are usually constructed to conveniently lay apaved strip about 8 feet wide, the side wall means 24b, 24c may bespaced about 8 feet apart from each other. The hopper 24 may be about 4feet wide, for example, measured from the front surface of front framemember 200 to the rear surface of rear end wall means 24a. In order toenlarge upon the capacity of hopper 24 and/or to facilitate positioningthe rear portion of an usually wide truck bed between the upper portionsof the side wall means 24b, 24c, movable auxilary side wall panels 24b,240' may be pivotally connected to upper portions of side wall means24b, 24c, respectively, for adjustment about substantially horizontalaxes. The rear portions of panels 24b, 24c are provided with arcuateplates 45 extending inwardly therefrom and engaged by respective hookmembers or fasteners 46 mounted for longitudinal adjustment in tubularmembers 47 carried by the rear upper portions of side wall means 24b,24c. The rear ends of hook members 46 have internally threaded cranks 50threaded thereon. Cranks 50 are adapted to be rotated by the operator totighten and loosen the corresponding hook members 46 relative to thearcuate plates 45 to facilitate adjusting the auxilary side wall members24b, 24c inwardly and outwardly relative to the side wall means 24b,240.

When hopper 24 is substantially filled with paving material, it ispreferred that the center of gravity of the entire paving machine islocated adjacent to and forwardly of the drive wheel axles 26, 26a.Therefore, to insure that an excess amount of paving material is notdisposed rearwardly of the desired center of gravity, it is preferredthat the rear end wall means is inclined upwardly and forwardly at ashallow angle relative to the vertical of about to The lower portion ofrear end wall means 24a has a downwardly and forwardly inclined bibportion 24a thereon which partially underlies auger means to be laterdescribed.

The lower wall means 44 includes a downwardly and rearwardly inclinedbottom wall panel 54. In the first embodiment of FIGS. l-lS, oppositeside portions of panel 54 are removably secured to side wall means 24b,240 by means of screws 55. The inclined bottom wall panel 54 extendsover drive wheels 21, 21a with its lower edge spaced forwardly from therear end wall means 24a to define an elongate discharge opening 56therebetween through which paving material is discharged from hopper 24to fall onto the surface to be paved. Opposing side areas of dischargeopening 56 are selectively opened and closed by gate means includingright-hand and left-hand substantially aligned, discharge gates 57, 57a.The rear lower edge of inclined bottom wall panel 54 and the upperforward edges of gates 57, 57a are pivotally mounted on a pivot shaft 60(FIG. 8) extending through the rear portions of the wheel-mounting framemembers d, 20d (FIG. 14).

The discharge gates 57, 57a are power-operated but individuallycontrolled by an operator so that, if desired, one of the gates may beclosed while the other is opened to discharge paving material from onlyabout one-half of the width of the hopper 24. Also, discharge gates 57,57a may be opened during paving of a desired surface and, while thehopper still contains a supply of paving material, the gates may beclosed and the machine may be moved to another location, or for arelatively short distance, as desired, before again commencing thedepositing of paving material onto the surface therebeneath. To thisend, a separate power means including a fluid-operated gate ram 62, isconnected to each discharge gate exteriorly of the hopper.

As shown in FIG. 8, fluid-operated ram 62 is in the form of a cylinderover which lower wall means 44 normally extends and which contains asuitable piston, not

shown, to which a piston rod 65 is connected. The piston rod 65 ispivotally connected, as at 66, to a lower rear portion of thecorresponding gate 57 or 57a, as the case may be, and the cylinder ofram 62 is pivotally connected at its front portion, as at 67, to framemember 200. The two cylinders 62 are of the double-acting type and arecontrolled by respective manually operable, four-way control valves 70,a (FIG. 15) whose inlet conduits 71, 710 are connected to a highpressure manifold 72. Manifold 72 is connected to the output end of aconduit 73, whose input end is connected to the outlet of pump unit 31b.A manually operable switching valve 310 is connected across conduits 33,73 for purposes to be later described.

The control valves 70, 70a are manually controlled so as to selectivelydirect fluid, under pressure, although corresponding conduits d, e f,connected thereto. The other ends of conduits d, e, are connected toopposite ends of the corresponding right-hand and left-hand cylinders62. The conduits f extend from control valves 70, 70a to a commonexhaust or fluid returning, low pressure, manifold 75 connected, bymeans of a conduit 76, to the upper portion of reservoir 32.

The upper front extremity of inclined bottom panel 54 of lower wallmeans 44 terminates along a line spaced rearwardly from the verticalplane of front frame member 20a and has a pair of spaced apart shelves54b, 54b (FIGS. 1, 2 and 14), preferably formed integral therewith,extending forwardly therefrom and overlying the enlarged or higher outerportion of L-shaped reservoir 32 and motor 30, respectively. The frontend portions of shelves 54b, 54b have respective pairs of legs 54c, 546'secured thereto and depending therefrom, and which normally rest uponfront frame member 20a. Thus, the proximal edges of shelves 54b, 54bdefine a recess therebetween, opposed sides of which are closed byclosure plates 54d, 54d welded or otherwise suitably secured to theproximal edges of shelves 54b, 54b and the corresponding legs 54c, 54c.

To accommodate the rear portion of a standard dump truck, whose bed maybe relatively low and relatively narrow, for depositing the pavingmaterial in hopper 24, a substantially L-shaped receptor 54c normallyfits loosely between closure plates 54d, 54d and has the upper edge ofits rear panel portion hingedly or pivotally connected to the exposedfront upper edge of a medial portion of inclined bottom panel 54. Sincethe front edge of the bottom panel of receptor 542 is of relatively thinsheet metal, the front edge thereof may be reinforced by a reinforcingbar or lip 54f.

Receptor 54c serves to collect therein any paving material which spillsoff the truck bed positioned thereover without being deposited on theinclined bottom wall 54 and, after the truck has withdrawn from thepaving machine, receptor 54 may be pivoted upwardly and rearwardly tothe position shown in FIG. 7 so that the contents thereof may slide outof the receptor and onto the inclined bottom panel 54. Additionally, thereinforcing bar 54f on the front edge of the bottom panel of receptor54c serves to restrain either .a standard size dump truck or a tandemwheel dump truck from accidentally moving away from the paving machineduring the transfer of paving material from a truck bed into hopper 24and while the paving machine is being moved over and depositing pavingmaterial on the surface being paved. In this regard, it will be notedthat front end frame member 20a is provided with a pair of spaced apart,substantially axially aligned and elongate rollers 80, 80' thereon whichare adapted to engage the rear wheels of a truck T as shown in FIG. 3 sothat the paving machine pushes the truck along the surface to be pavedduring the transfer of paving material therefrom into hopper 24 andduring the paving operation.

The lower surface of receptor 54e normally rests on a pair of posts 54gon frame member 200. In order to raise and lower receptor 54e betweenthe positions shown in FIGS. 6 and 7, and to also raise the receptor 54efrom its normal lowered position of FIG. 6 to a position where itsreinforcing bar 54f will engage a lower portion of the truck bed or itsrear springs forwardly of the rear spring shackles thereof, in the firstembodiment the lower surface of the bottom panel of receptor 54enormally engages a cam plate 81 secured on or formed integral with areceptor actuator arm 82. Arm 82 normally extends downwardly andforwardly and is pivotally connected, as at 83, to bracket 23a (FIGS. 6and 7). Adjacent its free end, a piston rod 84 of a double-actingreceptor ram or cylinder 85 is pivotally connected to actuator arm 82.Piston rod 84 is connected to a piston within cylinder 85, and the endof cylinder 85 remote from actuator arm 82 is pivotally connected as at86, to a lower front portion of frame member 20c. Thus, lower wall means44 normally extends over cylinder 85.

Receptor 54s is controlled by a manually operable control valve 87,which may be of the same type as valves 35, 35a, and whose inlet isconnected to high pressure manifold 72 by means of a branch conduit 87a(FIG. Conduits g, h, i, into which fluid is directed in a selectivemanner by the operator, lead from control valve 87a. Conduits g, h, areconnected to opposite ends of cylinder 85, and conduit i is connected tolow pressure manifold 75.

When control valve 87 is manipulated by the operator to introduce fluidpressure into the lower or rear portion of cylinder 85, piston rod 84moves actuator arm 82 upwardly and forwardly the desired distance so asto either cause reinforcing bar 54f to engage the lower portion of atruck bed in the manner heretofore described, or to cause actuator arm82 to move to its full forward position shown in FIG. 7. When piston rod84 is being fully extended, the actuator cam 81 moves receptor 54eupwardly a predetermined distance, whereupon it tightens a normallyslack pliable element or chain 90 removably connected to and extendingbetween actuator arm 82 and an arm 91 secured to and extendingrearwardly from the substantially vertical panel of receptor 54e whenreceptor 54e occupies its normal fully lowered position.

Such tightening of chain 90, and the consequent forward pull imparted tochain 90 by actuator arm 82 swings receptor 54a upwardly and away fromcam 81 until the former rear panel thereof is substantially aligned withthe inclined bottom panel 54 as shown in FIG. 7. As receptor 54e reachesthe fully raised position of FIG. 7, a leaf spring member 92, secured tothe rear panel thereof, engages and is biased by the upper surface ofinclined bottom panel 54. The leaf spring member 92 thus provides meansfor initiating the return of receptor 54e from the fully raised positiontoward the lowered position when the flow of fluid pressure intocylinder 85 is reversed and consequent slackening of chain occurs. Thus,with further retraction of piston rod 84 into cylinder 85, receptor 54efalls onto cam 81 and thus may return to fully lowered position with cam81 and actuator arm 82. Whenever lower wall means 44 is to be raised tothe position of FIG. 8, it is apparent that bolts 55 (FIGS. 1 and 2) maybe removed from side wall means 24b, 24c, and chain 90'is detached fromactuator arm 82.

ROTARY AUGER MEANS A rotary auger means is provided in the lower rearportion of hopper 24, above and adjacent discharge opening 56, to aid inuniformly distributing the paving material from side to side in hopper24 when desired. More importantly, the auger means facilitates feedingpaving material to screed extensions to be later described. The rotaryauger means comprises right-hand and left-hand distributing augers 100,a whose proximal end portions are journaled in suitable bearings carriedby middle frame members 20e in the first embodiment of the pavingmachine. The outer end portions of the augers 100, 100a, adjacent therespective side wall means 24b, 24c of hopper 24, are journaled inrespective bearing brackets 103, 103a (FIG. 5) which extend upwardlyfrom the shafts of augers 100, 100a and are welded or otherwise suitablysecured to side wall means 24b, 240. The proximal portions of the shaftsof augers 100, 100a, and frame member 20e, are positioned within ahousing 104 normally closed by a substantially L-shaped cover 104 whichserves normally as part of lower wall means 44 and whose opposing endportions are removably secured, as by screws 104a, to the rear end wallmeans 24a and the inclined bottom panel 54, respectively, of hopper 24.Cover 104 is removed from housing 104 whenever lower wall means 44 is tobe raised to the position of FIG. 8. Within housing 104, the shafts ofaugers 100, 100a are engaged by respective sprocket wheels j, k (FIG. 5)on which respective endless sprocket chains 1, m are mounted as bestshown in FIGS. 5, 6 and 7. Sprocket chains 1, m extend forwardly througha suitable opening provided in the lower portion of bottom wall panel 54and are mounted on respective sprocket wheels n, 0, driven by respectivefluid-operated auger motors 105, 105a. The auger motors are mounted onplatform 20f in the first embodiment (FIGS. 5 and 14).

Fluid-operated motors 105, 105a are reversible and are controlled byrespective manually operable control valves 106, 106a (FIG. 15), each ofwhich has a plurality of conduits p, q, r, connected thereto and leadingtherefrom. Conduits p are connected to manifold 72 and conduits s areconnected to manifold 75. Conduits q, r of valves 106, 106a areconnected to opposite sides of the respective auger motors 105, 105a.Valves 106, 106amay be of the same type as those manually controlledvalves heretofore described and may be manually manipulated to driveaugers 100, 100a at the desired speed and in the desired directionindependently of each other. The auger motors 105, 105a may be of a typemanufactured by Char-lynn' Company, Eden Prairie, Minn. under Model .No.18S having a torque rating of about 200 foot-pounds.

Referring to FIG. 15, since pump unit 32b provides fluid pressure foroperating both auger drive motors 105, 105a through the respectivecontrol valves 106, 106a, there is incorporated-in the auger drive aselfequalizing principle to the extent that, the greater the torque loadon one auger relative to that on the other auger, the greater is thedifferential speed therebetween. This occurs because a greater amount offluid will flow, per unit of time, through that motor whose auger isunder a relatively light torque load than that which will flow throughthe other auger motor whose auger is under a relatively heavy torqueload. Such a condition may occur, for example, as a result of one augerhaving more tightly compacted a mass of paving material against itsadjacent hopper side wall means or the adjacent gauge sled member, to belater described, than that compacted, if at all, by the other augeragainst its adjacent side wall means or gauge sled member.

Such condition also may occur if rotation of one only of the augers isobstructed by a rock or other foreign object in the paving material. Inthe latter instance, the obstructed auger then may stop rotation and theunobstructed auger would then rotate at about twice its normalrotational speed. In order to dislodge the obstruction, such as bycrushing the same between the auger and the rear end wall means 24a orthe bib portion 24a thereof, the operator may close the auger controlvalves 106, 106a to stop rotation of both augers 100, 100a and then openor jog that control valve which controls rotation of the then obstructedauger to greatly increase the rotational force transmitted thereto bythe corresponding auger drive motor. Also, the direction of rotation ofthe corresponding auger may be readily reversed by manipulation of thecorresponding auger control valve to facilitaate dislodging theaforementioned rock or foreign object from the obstructed auger so thatthe rock or foreign object will then fall through the hopper dischargeopening 56 and onto the surface being paved.

To avoid fracturing the obstructed auger or adjacent components of thepaving machine in the event that the rock or other foreign object cannotbe crushed, mutilated or dislodged from the obstructed auger upon apredetermined safe maximum rotational force being applied to theobstructed auger, a pre-adjusted bypass safety valve 110 (FIG. 15) ofconventional or other construction is interposed in the fluid pressurecircuit between the output side of the pump unit 31b and tank 32. Asshown in FIG. 15, bypass safety valve 110 is interposed in a fluidconduit line 11] extending from the high pressure manifold 72 to returnconduit 76. Upon build-up of pressure in the high pressure conduit 72 toa predetermined maximum, as may occur upon existence of the lastmentioned condition of an obstructed auger, bypass valve 110 opensautomatically to permit the fluid being discharged from pump unit 31b tobypass the valves connected to high pressure manifold 72 and to returnto the reservoir or tank 32.

In the event of both sets of drive wheels 21, 21a being obstructed, orone of the control vales 35, 35a therefor being closed and the other ofthe latter valves being opened to drive an obstructed set of the drivewheels, a bypass safety valve 112, interposed between the high pressureconduit 33 and the lower pressure or exhaust conduit 39, will operateupon a predetermined maximum pressure being present in the high pressureconduit 33 to return the fluid being discharged from the pump unit 31ato the reservoir or tank 32 and thereby avoid fracture or other damageto the drive wheel axles 26, 26a or to the drive mechanism connectedthereto.

SCREED MEANS The screed means 25 comprises an elongate, relativelynarrow, main screed 25a of hollow construction and of a length about thesame as that of the width of main frame 20 and hopper 24 when measuredparallel to the rotational axis of drive wheels 21, 21a. Main screed 25is positioned rearwardly of and adjacent rear wall means 240 of hopper24, and the front wall of main screed 25a curves upwardly past the topwall of main screed 25a and is pivotally connected, as at 25b (FIGS. 6,7, 8 and 9), to a screed supporting lower frame memher 250. Frame member250 is secured to the rear surface of a lower guide member 25d abovewhich the upper front portion of frame member 250 extends. Guide member25d is suitably secured to the front lower portion of a substantiallyvertically disposed screed support plate 25 whose upper portion also hasan elongate guide member 25f, and an elongate upper frame member 25gsuitably secured thereto and corresponding to the respective members25d, 250.

The rear portion of main screed 25a is supported adjacent opposite endsthereof; i.e., adjacent opposite sides of the paving machine, by a pairof vertically adjustable links, each of which comprises a lowerinternally threaded link member 25h (FIGS. 6, 7 and 8) pivotallyconnected to the upper wall of main screed 25a and into which the lowerportion of a screw 25i is threaded. The upper portion of screw 25iloosely penetrates an upper sleeve member'25j pivotally mountedintermediate its end on the rear portion of a substantially horizontallydisposed arm 25k whose front end portion is welded or otherwise suitablysecured to frame member 25g. A hand crank 25m is fixed on the upper endof each screw 251'. Thus, by rotating the hand cranks 25m, main screed25a may be pivotally adjusted to vary the angle of the lower surfacethereof, as de sired, relative to the surface to be paved and thereby toobtain the desired density of the paving strip bieng formed.

Opposed end portions of screed support plate 25e project outwardly arelatively short distance beyond opposing sides of hopper 24 and havethe upwardly projecting rear ends of respective lever arms 25p, 25qfixedly secured to the front surface thereof (FIGS. l-5, 7 and 9). Leverarms 25p, 25q extend forwardly past opposing ends of the two sets ofdrive wheels 21, 21a and have their front portions pivotally connectedto front frame member 200 of main frame 20, thus serving to stabilizemain screed 25a against any substantial lateral move-ment with therespect to the path of travel thereof with hopper 24.

Main screed 25a is suspendingly supported for substantially freevertical movement relative to hopper 24, and also may be raised andlowered varying distances through power means controlled by an operator.To this end, it will be observed in FIG. 2 that a right-hand portion offrame member 25 has a relatively short tubular guide member 117 suitablysecured thereon, which guide member is preferably of polygonal internalcross-section and has a mating slide bar 118 mounted therein andprojecting outwardly from opposite ends thereof. The end of the pistonrod 119 of a doubleacting screed lifting ram or cylinder 120 is suitablysecured to the right-hand end portion of slide bar 118 as shown in FIG.2, and the left-hand end of ram 120 is connected, as at 122, to framemember 253.

Opposite ends of slide bar 118 have corresponding ends of respectivepliable elements or cables 123, 123a attached thereto, both of whichextend to the left from the corresponding ends of slide bar 118, passbeneath and upwardly from respective pulleys 124, 124a and are connectedat their upper portions to respective arms 125, 125a. Arms 125, 125aextend forwardly and are suitably secured to upper portions of rear endwall means 24a of hopper 24. Pulleys 124, 124a are rotatably mounted insuitable brackets attached to upper screed supporting frame member 25g.

Opposite ends of cylinder 120 are connected by conduits u, v to theoutput side of a manually operable control valve 130 (FIG. 15). Controlvalve 130 may be of the same type as those heretofore described and alsohas a conduit w leading from the output side thereof to low pressuremanifold 75. Fluid pressure is directed to valve 130 by means of aconduit 131 extending between valve 130 and high pressure manifold 72.

It is thus seen that, by manipulating valve 130, piston rod 119 may beextended and retracted relative to cylinder 120 and, upon beingextended, piston rod 119 imparts left-to-right movement to slide bar 118in FIG. 2, thus moving the lower portions of cables 123, 123a therewithso that the pulleys 124, 124a will move upwardly along the verticalreaches of cables 123, 123a to raise main screed a. Obviously, uponpiston rod 1 19 being retracted, screed 25a may be lowered the desiredamount and to the extent of simply resting upon the surface to be pavedor the paving material being spread.

SCREED EXTENSIONS Fluid operated, extensible and retractable, righthandand left-hand screed extensions 140, 140a and associated gauge sledmembers 141, 141a are provided at opposite sides of main screed 25a.Only right-hand screed extension 140 and its gauge sled member 141 willbe described in detail with reference to FIG. 9, since, with theexception of left-hand screed extension 140a being oppositelyconstructed with respect to right-hand screed extension 140, they areessentially of the same construction. In order to direct paving materialfrom hopper 24 to screed extensions 140, 140a, the rear lower cornerportions of side wall means 24b, 240 are provided with respective sidedischarge openings 24e, 24f (FIGS. 1, 2 and 14) which may be about thesame size as or somewhat larger than the adjacent ends of augers 100,100a, although the lower portions thereof are partially-closed by therelatively narrow lower portions of lever arms 25p, 25q during normaloperation of the paving machine. The side discharge openings 24e, 24farealigned with augers 100, 100a so that the augers will force the pavingmaterial outwardly from the hopper through the openings 24e, 24f, andagainst the adjacent surfaces of the sled members 141,

141a to ensure that the paving material is of the desired density as itis being directed to the screed extensions 141, 141a.

As shown in FIG. 9, screed extension 140 comprises a substantiallyC-shaped compacting member or screed plate 140!) which looselypenetrates the adjacent side wall of main screed 25a and is slidablysupported on the bottom wall and against the front wall of main screed25a. Compacting member 140b extends upwardly between the top and frontwalls of main screed 25a and is slidable between guides 1400, 104dsuitably secured to the respective bottom and front walls of main screed25a.

A tubular guide member .140e is welded or otherwise suitably secured tolower supporting frame member 25c of main screed 25a and has anextension bar l40f mounted for longitudinal sliding movement therein. Abracket 140g serves to secure the outer or free end portion of extensionbar 140f to a substantially vertically disposed slide plate 140ksupported for longitudinal sliding movement between the guide bars 25d,25f carried by screed support plate 25e. A rearwardly projecting fingeror pin 140i is secured to the outer end portion of extension bar l40fand loosely penetrates a vertically extending slot 140j extendingthrough the substantially vertical outer end portion of compactingmember 140b.

.A double-acting fluid-operated, screed extension arm or cylinder 140kis mounted on and suitably secured to tubular guide member 140e. Theouter end of a piston rod of ram 140k is connected, as at 140n, to anouter end portion of extension bar l40f. A separate manually operablecontrol valve 140p, of the same general type as valve 35, is provided(FIG. 15) for control the flow of fluid to opposite ends of eachrespective fluidoperated ram or cylinder 140k. Each valve 140p hascorresponding ends of four conduits a-d' connected thereto, the otherends of conduits c, d being connected to the respective manifolds 72,75. The two pairs of conduits a, b connect valves 140p to the respectiveright-hand and left-hand screed extension cylinders or rams 140k sothat, by manual manipulation of control valves 104p, the screedextensions 140, 140a may be telescoped; i.e., extended and retracted,relative to main screed 25a, as desired, together or independently ofeach other.

All of the manually operable control valves 31c, 35, 35a, 70, a, 87,106, 106a, 130, p, 140:; are preferably suitably mounted on the rearsurface of rear end wall means 24a, as by means of a common bracket 143(FIG. 2), so as to be conveniently accessible to an operator standingupon main screed 25a, with adjacent portions of the fluid conduitsextending from the control valves being positioned in a suitable casing144 carried by rear end wall means 24a. As shown in FIG. 6, rear endwall means 24a is also provided with an opening 145 therethrough whichcommunicates with the interior of housing 104 so that most of the fluidconduits extending from the control valves may extend through housing104 to the pump means 31, reservoir 32, fluidoperated motors 36, 36a,105, 105a (FIG. 5), rams 62 (FIG. 3) and ram 85 (FIGS. 6 and 7) all ofwhich are positioned substantially within the vertical plane of hopper24 and are normally covered by lower wall means 44.

Gauge sled member 141 comprises a substantially vertically disposedpaving retaining or shield plate 141b having a runner 14lc defining thelower edge thereof and being curved upwardly at its front portion tofacilitate sliding movement of runner 1410 over the surface to be paved.The rear end portion of shield plate 141b preferably terminates insubstantial alignment with or forwardly of the rear end wall of mainscreed 25a, and the front edge of shield plate 14lb terminates forwardlyof the lateral plane of the adjacent side discharge opening 24e. Also,the height of at least the forward portion of shield plate 14% should besuch that its upper edge will be disposed above the level of the upperextremity of the adjacent side discharge opening 24c whenever runnerl41c is engaging the ground adjacent the surface to be paved, whileallowing for various thicknesses of paving material to be spread uponthe surface.

Means are provided for pivotally connecting gauge sled member 141 to,and for facilitating vertical adjustment of gauge sled member 141relative to, the outer end portion of the corresponding screed extension140. To this end, a medial portion of shield plate 14lb has a verticallyextending adjustment slot 141d (FIG. 9) therethrough, through which apivot pin 141e loosely extends and is pivotally embedded in the outerend of extension bar 140f, preferably by being threaded thereinto. Theouter portion of pivot pin 141e is suitably secured to or formedintegral with a block 141f having a substantially vertically extending,externally threaded post or rod 141g integral therewith or otherwisesuitably secured thereto. Threaded rod 141g is engaged by an internallythreaded sleeve 141h whose upper portion is rotatably mounted in andsuitably restrained from axial movement in an angle bracket 141i weldedor otherwise suitably secured to the upper portion of shield plate 14lb.A hand crank 141j is connected to the upper end of internally threadedmember 141k to facilitate adjusting the same to raise and lower theshield plate l41b and its runner 141s relative to its pivot pin 141eand, thus, relative to the corresponding screed extension 140.

METHOD OF OPERATION For purposes of this disclosure, it may be assumedthat the fluid system described heretofore is a hydraulic system andthat motor 30 is rated at about 13 horsepower at 3,600 revolutions perminute and is normally operated at about 2,200 revolutions per minute,at which speed the output of pump units 31a, 31b may be about l and 13gallons per minute, respectively, at up to about 1,500 or more poundsper square inch gauge pressure. However, with both augers 100, 100aoperating under about the same torque load relative to each other, andwith both sets of drive wheels 21, 21a operating under about the sametorque load relative to each other, each of the drive motors 36, 36a,105, 105a may be subjected to a fluid pressure of about 700 to 800pounds per square inch.

In actual operation of a paving machine constructed according to thisinvention, and utilizing the fluid pressures last described above, thenormal paving speed of the machine was about 32 feet per minute with theaugers 100, 100a rotating at a speed of about 35 revolutions per minute.However, when the paving machine is to be moved from place to placeunder its own power without dispensing paving material from the hopper24 thereof, the mechanisms controlled by those valves connected tomanifolds 72, 75 (FIG. 15) need not be operated. Therefore, the manuallyoperable switching valve 31c, which is closed otherwise, may be operatedto switch the fluid output of pump unit 31b to that of pump unit 31a andthereby substantially increase the rate of flow of the fluid through thedrive wheel motors 36, 36a. This may more than double the linear speedof the paving machine over the ground without changing the output speedof motor 30. In the actual machine a speed of 74 feet per minute wasobtained.

Assuming that main screed 25a or the sled members 141, 141a are restingupon the ground, the screed lift control valve 130 (FIG. 15) is operatedmanually, be-

fore the switching valve 31c is moved to the latter position, so as toraise screed means 25 to a convenient transportable position, such asthat shown in FIG. 7. Also, screed extension control valves 140p, 140qmay be operated, if desirable, to fully retract screed extensions 140,140a so that the side discharge openings 24, 24f(FIGS. 1 and 2) will besubstantially closed as the shield plates 14lb engage lever arms 25p,25:

Of course, if the paving machine is to be moved a considerable distance;e.g., several miles, switching valve 31c may remain in that position inwhich it causes the fluid to flow from pump unit 31 to manifold 72, andinstead, the motor 30 would be shut off and the shipper handles 42mwould be moved outwardly from the position of FIG. 11 so as to disengageboth of clutches 42. By connecting a suitable draft bar to the front endof the paving machine and to a pulling vehicle in the manner heretoforedescribed, and with the screed means 25 occupying the raised position ofFIG. 7, the paving machine then may be pulled to any desired location byany suitable powered vehicle, thus obviating the need for loading themachine on a special trailer or turck to transport the same over longdistances.

Upon reaching the paving site, the draft bar is removed from the frontend of the paving machine, and the shipper handles 42m are returned tothe position shown in FIG. 11 to re-engage the clutches 42. Motor 30then is started and, with switching valve 31c closed, control valve 130is manually operated to partially lower screed means 25, if desired, toa more convenient position so that the operator may mount and stand onmain screed 25a. The operator then manipulates the drive wheel controlvalves 35, 35a (FIG. 15), to drive the paving machine forwardly orrearwardly, as desired, to position the same over the surface to bepaved. It should be noted that control valves 35, 35a also are used tosteer the paving machine by relatively varying the amount of fluiddirected to the motors 36, 36a sufi'iciently to overcome torque limiter40 and thereby vary the speed and/or direction of rotation of therespective sets of drive wheels 21, 210 relative to each other whendesired.

A truck then may be backed up to the front end of hopper 24 to dump asupply of paving material into hopper 24 with the truck bed overlyingthe front por tion of the lower wall means 44 of hopper 24 in the mannerheretofore described. The level of shelves 54b, 54b should be such as topermit the rear portion of the bed of a relatively large, so-calledtandem-wheel dump truck to pass thereover. Regardless of whether. thedump truck is of the standard or large size described, since thecapacity of the bed of the truck may be substantially greater than thecapacity of hopper 24, it usually is desirable to have the rear portionof the truck bed overlie the front portion of thelower wall means 44 ofhopper 24 during the paving operation. In this instance, the rear wheelsof the turck T (FIG. 3) are brought into engagement with the rollers 80,a, and the operator then manipulates receptor control valve 87 to causeactuator cam 81 (FIGS. 6 and 7) to push the receptor 54e upwardly sothat the reinforcing bar 54f thereon is yieldably urged against thelower surface of a rear portion of the truck bed or frame, preferablyimmediately forwardly of the rear spring shackels as shown in FIG. 3.Because of the compact construction of the paving machine, the distancefrom the front of rollers 80, 80a to the axis of augers 100, a, or tohopper discharge opening 56, may be 4 feet or less, thereby ensuringthat the paving material may be dumped from conventional size dumptrucks directly onto the augers above the discharge opening throughwhich the paving material gravitates directly onto the surface beingpaved. This has not been practicable heretofore to my knowledge.

With truck T in the position of FIG. 3, hand cranks 25m (FIG. 2) thenmay be adjusted to position the lower surface of main screed 25a at thedesired angle so as to obtain the desired compaction of the pavingmaterial to be deposited on the surface thereben eath, and hand cranksl4lj are rotated to position the lower surfaces of the runners 1410 ofgauge sled members 141, 141a the desired distance below the level of thelower surface of main screed 25a in accordance'with the desiredthickness of the paving material to be spread. It may be desirable toform a feather edge on either or both side portions of the paving strip,in which instance the corresponding gauge sled member or members may beadjusted upwardly relative to the main screed 25a so that thecorresponding runner or runners thereof are positioned at or above thelevel of the lower surface of main screed 25a.

In either event, screed means 25 then is lowered to the desiredposition, either with the runners 1410 resting upon the ground, or withthe lower surface of main screed 25a occupying a predetermined distancespaced above the ground in the event of the lower surfaces of the gaugesled members being disposed above the level of the lower surface ofscreed 25a. If the paving strip to be formed is to extend the full widthof hopper 24, both of the discharge gates 57, 57a are then opened in themanner heretofore described by manipulation of control valves 70, 70a.The operator then manipulates control valves 35, 35a to drive the wheels21, 21a and thereby perform the paving operation, during which thepaving machine pushes the truck T in front of the same and also duringwhich the reinforcing bar 54f on receptor 54e prevents the truck T frommoving forwardly away from the paving machine, even though the rearportion of the truck chassis may tilt upwardly or downwardly relative tothe paving machine because of the truck starting to move along anincline before such incline is reached by the paving machine.

The augers 100, 100a generally need not be rotating during paving if thescreed extensions 140, 104a and sled members 141, 141a are fullyretracted, since the paving material in hopper 24 is usuallysatisfactorily distributed when it is deposited therein by a dump truck.If the paving machine is moving along over a steeply laterally inclinedsurface, such that the paving material may gravitate toward the lowerside of the hopper, then it may be desirable to operate one or the otheror both of the augers 100, 100a to redistribute the paving material.However, rotation of augers 100, 1000 is desirable, if not necessary,when the respective screed extensions 140, 140a are extended to increasethe width of the paving strip being formed.

It is apparent that, if the paving strip is to be extended outwardly inwidth relative to either side of the hopper 24, the respective screedextensions 140, 140a may be adjusted outwardly by manual manipulation ofthe corresponding control valves 140p, 1401; (FIG. More importantly, thepowered operation of screed extensions 140, 140a facilitates the formingof a paving strip of progressively increasing width, for example,without the necessity of repeatedly stopping the paving machine andwithout the operator necessarily stepping off the main screed 25a toadjust the screed extensions. For example, the major portion of a pavedstrip being formed may be of about the same width as the hopper 24;e.g., about 8 feet wide, with the screed extensins 140, 140a and thegauge sled members 141, 141a occupying fully retracted position.However, by manual manipulation of screed extension valves 140p of FIG.15, both screed extensions 140, 140a may be moved outwardlyprogressively in relatively small increments, if desired, during theforward travel of the paving machine to provide a somewhat tapered orcurved and gradually increasing width to the paving strip being formedand so that the width of the enlarged portion of the paving strip may beup to about 12 feet wide, for example. Of course, it is apparent thatonly one of the screed extensions 140, 140a and the adjacent auger needbe operated if it is desirable to increase the width of the paving stripat one side only thereof.

In some instances, as in paving an automobile parking area, for example,it may be desirable to move the truck T (FIG. 3) away from the pavingmachine after the hopper 24 has been filled with paving material,especially if the parking area is so confined that the truck could notbe accommodated in front of the paving machine as it approached the endof the laying of a particular strip of paving material. Also it isobviously necessary for the truck to be moved away from the pavingmachine when the truck must replenish its supply of paving material. Ineither instance, in the event that any of the paving material beingtransferred from the truck bed into the hopper may have accumulated inreceptor 54c, receptor 54e may be moved upwardly to the position of FIG.7, in the manner heretofore described, to transfer any paving materialtherein onto the inclined bottom panel 54 of hopper 24, after whichreceptor 54e may be returned to its normally lowered position shown inFIG. 6.

In the paving of rather restricted areas, such as parking lots, thepaving machine disclosed herein has many advantages over other pavingmachines proposed heretofore. One such advantage is, of course, thecompact construction of the paving machine, but more importantadvantages reside in the facility with which the paving machine may beturned around to face in the opposite direction upon completion of theformation of a given paving strip and preparatory to the formation ofanother immediately adjacent paving strip. In carrying out thisprocedure, after a supply of paving material has been deposited inhopper 24 and the truck has moved away from the paving machine, receptor54e may be raised from the position of FIG. 6 to that of FIG. 7 and thepaving machine is propelled under its own power to lay a first strip ofpaving material on the surface to be paved, during which the screedmeans 25 occupies the lowered position shown in FIG. 6 and is supportedby means of the gauge sled members 141, 141a sliding upon the ground.Both discharge gates 57, 57a would be opened, and both sets of drivewheels 21, 21a would be driven in the manner heretofore described. Also,if both extensions 140, 140a have been extended, both augers 100, awould be driven.

Upon reaching the end of the laying of the first paving strip, theoperator may manipulate valves 70, 70a, to close the discharge gates 57,57a, and raise main screed 25a, screed extensions 140, a and gauge sled

1. A self-propelled paving machine comprising a frame, a plurality ofsubstantially axially aligned drive wheels supporting said frame formovement over a surface to be paved, motive means carried by said frame,drive mechanism connecting said motive means to said drive wheels andalso carried by said frame, a hopper carried by saId frame and adaptedto receive paving material therein, a lower portion of said hopperrearwardly of said drive wheels having a discharge opening therein fordischarging paving material from said hopper onto the surface to bepaved, a substantially vertically movable main screed carried by saidpaving machine and positioned rearwardly of said hopper for smoothingand compacting the paving material during movement of the machine overthe surface to be paved, a screed extension carried by at least one sideportion of said screed, power means for extending and retracting saidscreed extension relative to said main screed, manually operable controlmeans operatively connected to said power means for controlling thesame, a substantially vertically disposed shield plate carried by andpositioned adjacent the outer end of said screed extension, said hopperhaving side wall means provided with a side delivery opening thereinadjacent said screed extension, and a rotary auger in said lower portionof said hopper for forcing paving material therein outwardly throughsaid side delivery opening and against said shield plate to be smoothedand compacted upon said surface by said screed extension.
 2. A structureaccording to claim 1, including drive means drivingly connected to saidrotary auger for rotating the same and including means responsive topredetermined compaction of paving material against said shield plate bysaid auger for stopping rotation of said auger.
 3. A self-propelledpaving machine comprising a frame, a plurality of substantially axiallyaligned drive wheels supporting said frame for movement over a surfaceto be paved, motive means on said machine, drive mechanism connectingsaid motive means to said drive wheels and carried by said frame, ahopper carried by said frame and adapted to receive paving materialtherein, a lower portion of said hopper rearwardly of said drive wheelshaving a discharge opening therein for discharging paving material fromsaid hopper onto the surface to be paved, a truck engaging means carriedby a front portion of said frame and adapted to engage a rear portion ofthe truck for pushing the same during a paving operation, a lip mountedfor vertical movement on a forward portion of said paving machine, and amanually controlled fluid operated ram interposed between said frame andsaid lip for raising and lowering said lip into and out of engagementwith a lower surface of a portion of the truck overlying said lip andcausing said lip, when raised, to engage said lower surface underpressure such that said lip will apply braking force to the truck toprevent the rear portion thereof from moving away from said truckengaging means during a paving operation.
 4. A compact self-propelledpaving machine comprising a frame, a plurality of drive wheelssupporting said frame for movement over a surface to be paved, motivemeans carried by said machine, drive mechanism connecting said motivemeans to said drive wheels and carried by said frame, a hopper carriedby said frame and substantially completely overlying said drivemechanism and said drive wheels, a lower portion of said hopperrearwardly of said drive wheels having a discharge opening therein fordischarging paving material from said hopper onto the surface to bepaved by gravity, said drive mechanism and said drive wheels beingcompactly arranged whereby the rear portion of a conventional dump truckmay overly a front portion of said hopper and paving material may bedumped from the truck to gravitate directly from the truck toward saiddischarge opening, said hopper comprising substantially upright rear endwall means and spaced side wall means, a lower wall means defining thebottom of said hopper and including a downwardly and rearwardly inclinedbottom panel extending between said spaced side wall means, said bottompanel extending over and across said drive wheels with its lower rearedge spaced forwardly from said rear end wall means to define saiddischarge openinG therebetween, said lower wall means further comprisinga receptor adapted to receive thereover a lower rear portion of a truckbed, said receptor including a bottom panel normally occupying asubstantially horizontal position, means pivotally supporting a rearportion of said receptor for vertical pivotal movement relative to saidinclined bottom panel, and manually controlled power means operativelyassociated with said motive means for raising said receptor about itspivot whereby any paving material deposited thereon may be caused togravitate toward said discharge opening when the truck bed is removedfrom over said receptor.
 5. A structure according to claim 4, whereinsaid manually controlled power means for raising said receptor comprisesa fluid-operated pump means driven by said motive means, afluid-operated ram interposed between said frame and said receptor andconnected to said pump means, and manually operable valve meansinterposed in a fluid pressure circuit between said ram and said pumpmeans for controlling the flow of fluid pressure to said ram.
 6. Acompact self-propelled paving machine comprising a frame, a plurality ofdrive wheels supporting said frame for movement over a surface to bepaved, motive means carried by said machine, drive mechanism connectingsaid motive means to said drive wheels and carried by said frame, ahopper carried by said frame and substantially completely overlying saiddrive mechanism and said drive wheels, a lower portion of said hopperrearwardly of said drive wheels having a discharge opening therein fordischarging paving material from said hopper onto the surface to bepaved by gravity, said drive mechanism and said drive wheels beingcompactly arranged whereby the rear portion of a conventional dump truckmay overly a front portion of said hopper and paving material may bedumped from the truck to gravitate directly from the truck toward saiddischarge opening, said hopper comprising a lower wall means definingthe bottom of said hopper, means pivotally supporting the rear portionof said lower wall means for angular movement about a pivot axisadjacent said discharge opening and extending substantially parallelwith said drive wheels, and means operatively associated with saidmotive means for pivoting said lower wall means about said pivot axis tovary the angular position of said lower wall means.
 7. A compactself-propelled paving machine comprising a frame, a plurality of drivewheels supporting said frame for movement over a surface to be paved,motive means carried by said machine, drive mechanism connecting saidmotive means to said drive wheels and carried by said frame, a hoppercarried by said frame and substantially completely overlying said drivemechanism and said drive wheels, a lower portion of said hopperrearwardly of said drive wheels having a discharge opening therein fordischarging paving material from said hopper onto the surface to bepaved by gravity, said hopper comprising substantially upright rear endwall means and spaced side wall means, a lower wall means defining thebottom of said hopper and including a downwardly and rearwardly inclinedbottom panel extending between said spaced side wall means, said bottompanel extending over and across said drive wheels with its lower rearedge spaced forwardly from said rear end wall means to define saiddischarge opening therebetween, said drive mechanism and said drivewheels being compactly arranged whereby the rear portion of aconventional dump truck may overly a front portion of said hopper andpaving material may be dumped from the truck to gravitate directly fromthe truck toward said discharge opening, and means pivotally connectingthe rear lower portion of said inclined bottom panel to said frame alongan axis rearwardly of and substantially parallel to the axis of saiddrive wheels whereby said lower wall means may be tilted upwardly aboutthe pivot point of said bottom panel to facilitate access to said drivemechanism and said drivE wheels therebeneath.
 8. A structure accordingto claim 7, wherein said motive means comprises an internal combustionmotor on a front portion of said frame, a fluid reservoir carried by afront portion of said frame, and pump means driven by said internalcombustion motor, all normally positioned under said lower wall means,said drive mechanism including hydraulic motor means drivingly connectedto said drive wheels, fluid conduit means connecting said pump means tosaid reservoir and said hydraulic motor means, control valve means insaid conduit means between said pump means and said hydraulic motormeans, and said hopper lower wall means further comprising meansintegral with and projecting forwardly from said inclined bottom paneland normally overlying said internal combustion motor and said reservoirto shield the same from paving material deposited on said lower wallmeans and whereby said lower wall means also may be tilted upwardly tofacilitate access to said internal combustion motor and said reservoir.9. A compact self-propelled paving machine comprising a frame, aplurality of drive wheels supporting said frame for movement over asurface to be paved, motive means carried by said machine, drivemechanism connecting said motive means to said drive wheels and carriedby said frame, a hopper carried by said frame and substantiallycompletely overlying said drive mechanism and said drive wheels, a lowerportion of said hopper rearwardly of said drive wheels having adischarge opening therein for discharging paving material from saidhopper onto the surface to be paved by gravity, said drive mechanism andsaid drive wheels being compactly arranged whereby the rear portion of aconventional dump truck may overly a front portion of said hopper andpaving material may be dumped from the truck to gravitate directly fromthe truck toward said discharge opening, rotary auger means disposed insaid lower portion of said hopper to aid in laterally distributing thepaving material received thereon for discharge through said opening,additional manually controlled drive mechanism carried by said frame andconnecting said motive means to said auger means for rotating the same,said rotary auger means comprising a pair of first and secondsubstantially axially aligned augers each extending throughoutsubstantially one-half of the width of said hopper, a fluid pressurepump means driven by said motive means, and said additional manuallycontrolled drive mechanism comprising first and second fluid-operatedmotors communicatively connected to said pump means, and means drivinglyconnecting said first and second fluid-operated motors to the respectivefirst and second augers independently of each other.
 10. A compactself-propelled paving machine comprising a frame, a plurality of drivewheels supporting said frame for movement over a surface to be paved,motive means carried by said machine, drive mechanism connecting saidmotive means to said drive wheels and carried by said frame, a hoppercarried by said frame and substantially completely overlying said drivemechanism and said drive wheels, a lower portion of said hopperrearwardly of said drive wheels having a discharge opening therein fordischarging paving material from said hopper onto the surface to bepaved by gravity, said drive mechanism and said drive wheels beingcompactly arranged whereby the rear portion of a conventional dump truckmay overly a front portion of said hopper and paving material may bedumped from the truck to gravitate directly from the truck toward saiddischarge opening, screed means mounted for substantially free verticalmovement on said frame and positioned rearwardly of said dischargeopening in said hopper for smoothing and compacting the paving materialas said paving machine moves over the surface to be paved, said screedmeans comprising a main screed extending widthwise of and being ofsubstantially the same length as the width of said hopper, a screedextension mounted on at least oNe side portion of said main screed forinward and outward movement relative thereto, manually controlledfluid-operated means for selectively imparting predetermined inward andoutward movements to said screed extension, a sled member proximate tothe outer end of said screed extension and movable inwardly andoutwardly therewith, manually operable adjustment means for raising andlowering said sled member relative to said screed extension whereby saidsled member may serve to define the corresponding edge of the materialbeing spread, and said adjustment means including means pivotallyconnecting a medial portion of said sled member to said screed extensionand arranged to permit movement of said sled member about asubstantially horizontal axis whereby the position of said sled memberabout its axis may vary in accordance with the surface over which it ismoving in engagement therewith without being encumbered by said screedextension and said screed and without distrubing the position of saidscreed to any substantial degree when the sled member rides over arelatively small projecting irregularity in its path.
 11. Aself-propelled paving machine for cooperating with an automotive truckhaving a dump body for transporting paving material and for deliveringpaving material from the rearward end of the dump body, the pavingmachine comprising: a main frame, wheel means mounted on said frame forsupporting said frame on a surface to be paved, drive means mounted onsaid frame and operatively connected with said wheel means forpropelling the paving machine along the surface to be paved, hoppermeans mounted on said frame for containing paving material to be appliedand including wall means for defining a transverse slot through whichpaving material passes onto the surface to be paved, and coupling meansmounted from said frame in predetermined spaced relation to said hoppermeans for coupling together the paving machine and a truck and therebyfor enlarging the effective capacity of said hopper means by theaddition thereto of the effective capacity of the dump body of thetruck, and coupling means comprising: pushing means for engaging thetruck forwardly of the rearward end of the dump body and for limitingforward movement of said hopper means beneath the dump body by pushingthe truck upon forward movement of the paving machine, pivotal meansmounted at a forward edge of said hopper means for movement between aretracted position withdrawn from engagement with any overlying portionof a truck and an extended position in engagement with any overlyingportion of a truck for restraining the truck against forward movementotherwise removing the dump body from above said hopper means, and meansfor resiliently biasing the pivoted means toward the extended position,said coupling means and said hopper means cooperating for positioningsaid hopper means to underlie the rearward end of the dump body of atruck and to extend from a point forwardly thereof to a point rearwardlythereof during delivery of paving material from the dump body into saidhopper means, whereby paving material may be delivered from the dumpbody of a truck to which said paving machine is coupled by said couplingmeans simultaneously with passage of paving material through said hoppermeans and onto the surface to be paved.
 12. A self-propelled pavingmachine for cooperating with an automotive truck having a dump body fortransporting paving material and for delivering paving material from therearward end of the dump body, the paving machine comprising: a mainframe, wheel means mounted on said frame for supporting said frame on asurface to be paved, motive means mounted on said frame for supplyingmotive power to the paving machine, drive means mounted on said frameand operatively connected with said motive means and said wheel meansfor propelling the paving machine along the surface to be paved, hoppermeans mouNted on said frame for receiving and containing paving materialto be applied, said hopper means overlying said wheel means andincluding a generally vertical stationary rear wall having apredetermined transverse width, spaced apart side walls extendingperpendicular to said rear wall at the side edges thereof, and bottomwall means extending between and cooperating with said rear wall andsaid side walls, said bottom wall means comprising a trailing portionand a leading portion, each of said portions having a widthsubstantially the same as said rear wall and being mounted for pivotalmovement relative thereto about a common transverse axis spacedforwardly of said rear wall, said trailing portion extending rearwardlyfrom said transverse axis and defining with said rear wall a transverseslot through which paving material passes onto the surface to be paved,and said leading portion extending forwardly from said axis to underliepaving material delivered from a truck, first manually controlled fluidpressure operated means operatively connected with said motive means andsaid trailing portion for imparting angular movement thereto about saidaxis and thereby varying the width of the transverse slot definedbetween said rearward wall and said trailing portion, and secondmanually controlled pressure fluid operated means operatively connectedwith said motive means and said leading portion for imparting angularmovement thereto about said axis and thereby for aiding gravitationalflow of paving material received from a truck toward said transverseslot.